One of the best things about New York is that you can almost always hail a taxi, but good luck finding one willing to take you to Brooklyn. It seems that whenever it's raining or you need to cross a bridge, all of NYC's 13,000 taxis are already taken or magically disappear. But we hope Uber's recent expansion into the Big Apple will give commuters a viable option to go where taxis fear to tread.

The battle is on for two transportation network start-ups that are poised to go head-to-head at SXSW to promote a very similar business model: using an app to book a ride from a network of private cars.

Uber, a mobile limousine-booking service, has become a favorite among in-the-know techies in San Francisco. Launching its service in New York, where taxis are heavily regulated and easy to find already, may prove more complicated.